“Good friend, first consider one of the things I have noted, for it explains the shallows“.
Piri Reis, introductory poem to the Kitab al-Bahriye.
The great Turkish seafarer Piri Reis, in his book Kitab al-Bahriye, or Book of Navigation (1521), describes the waters and ports of the Mediterranean. Reading this book led me to a very simple observation, which could provide insight into one of the roundels of the nine-rosette foldout. .
Portolan charts have already been mentioned by others in comparison with the Voynich 9 rosette foldout page, but the quest to match the castles and structures to specific places has led to a neglect of the language of maps itself: topographic markings. I believe one of these markings can shed light on a small but significant aspect of the Voynich upper right rosette, where a castle is depicted.
Many have noted that the castle appears to be by the sea, and indeed there are wave-like forms beyond what appears to be a breakwater. However, at the center of the rosette, there are no waves: the area is marked by a field of asterisk-like stars. “The reason for this my friend is that there are never waves in these shallows… Because these seas are shallow, waves cannot extend: such places devour the waves“, Piri Reis explains.
In the Kitab al-Bahriye, dots represent places where the water is shallow, either sandy or with underlying reefs . Crosses represent areas where the water is not only shallow, but where the underlying rocks and/or reefs make it impossible for big ships to pass safely (Piri Reis does not distinguish between shallow rocks and reefs: both had the same effect on ships, which was his main concern). Of course, the Kitab al Bahriye was written almost a century after the Voynich manuscript. However, Piri Reis tells us that “Hidden reefs in the sea since ancient times have been shown by means of crosses“.
Indeed we find the crosses in many navigation maps from centuries prior, including the 13thC Carta Pisana, BNF Res. Ge. B1118, thought to be the oldest extant portolan chart, as well as in the 15thC Italian map labeled HM1548 at the Bancroft Library, among others.
The dots and crosses can be arranged in a linear fashion or to form various geometric motifs, but this in itself bears no significance, and the same harbor or bay can be shown on various maps with dots arranged either in lines or in circles or in other shapes.
Therefore, it is highly likely that the spiral impression in the Voynich illustration (which, by the way, only proceeds from the layout of the line of text, and not from the actual layout of the field of asterisks) is not significant: in actual maps, the geometric motifs formed by the marks serve purely aesthetic purposes such as in the examples from the Kitab al-Bahriye below.
My simple point in this post then is that if the 9-rosette foldout shows a map, then cartographic standards would lead me to interpret the field of asterisks as marking a shallow water area, possibly one which contains reefs or rocks.
Interestingly, to this day, the USGS and FAO use the exact same markings as those in the Voynich for exactly the same topographical feature!
If in fact the markings in the castle rosette are meant to convey the same thing as those on navigation maps, we can know one thing about the Voynich castle: Whether it is real or mythical, the waters there are shallow and possibly full of rocks, perhaps so much so that big ships cannot enter the bay.
I wouldn’t be surprised if the spiral line of text in the center contained words like “shallow”, “rocks” “reef”, or even “dangerous” …